Default parameter needs to be a string

DDG4/lcio/LCIOFileReader.cpp

@@ -131,6 +131,6 @@ dd4hep::sim::LCIOFileReader::readParticleCollection(int /*event_number*/, EVENT:
 /// list
 Geant4EventReader::EventReaderStatus
 dd4hep::sim::LCIOFileReader::setParameters( std::map< std::string, std::string > & parameters ) {
-  _getParameterValue( parameters, "MCParticleCollectionName", m_collectionName, LCIO::MCPARTICLE);
+  _getParameterValue( parameters, "MCParticleCollectionName", m_collectionName, std::string(LCIO::MCPARTICLE));
   return EVENT_READER_OK;
 }